Apparatus for drying filaments



2 SHEETSSHEET 1 J m u, m 1P 111:1151 LMWHJ m lti'orne APPARATUS FOR DRYING FILAMENTS Filed Dec. 29, 1948 Nov. 13, 1951. KULMAN 2,574,833

APPARATUS FOR DRYING FILAMENTS Filed Dec. 29, 1948 2 SHEETSSHEET 2 %57/ y 4 F1 4. BY 7 7 021% 77%- Patented Nov. 13, 1951 UNITED STATE S PATENT OFFICE AP PARATUS FOB DRYING FILAMENTS Application December 29, 1948, Serial No. 87,847

1 6 Claims.

In the manufacture, or.in the processing of synthetic or non-synthetic filaments, the filament is subjected to various liquid treatments, preferably while the filament is moving, in the form of several hundred percent of its weight, it is clear that adequate drying of the filament presents a difiicult problem. For example, using very intense heat may cause damage and lengthening the path of travel by enlarging the machine, or lengthening the time of travel of the filament in the drying zone by slowing its movement, so as to permit use of relatively moderate heat, will reduce the rate of production and will correspondingly increase the cost.

It is therefore the object of the invention to produce an improved method of, and apparatus for, drying a filament having a high moisture content while said filament moves at a relatively rapid rate, for a relatively short period of time, over a relatively short drying zone, and with the use of relatively moderate heat.

In the drawings:

Fig. 1 is a diagrammatic side elevational view of a synthetic thread manufacturing thread embodying my invention.

Fig. 2 is a view, partly in section and partly in elevation lookingin the direction of line 2-2 on Fig. 1.

Fig. 3 is an enlargement, partly in section and partly in elevation of the left hand end of Fig. 1.

Fig. 4 is a fragmentary view of a roll showing another embodiment of my invention.

The synthetic filament manufacture apparatus illustrated includes a spinnerette ll which extrudes an appropriate solution into an appropriate bath l! to form a synthetic filament. Instead of only producing a freshly coagulated synthetic filament, my invention can also'be used for processing an already manufactured filament. The filament, regardless of its nature or origin is passed over one or more godets l8 and through a guide It and is wound about one end of a thread storing and advancing reel formed of a plurality of rolls 2!. These rolls are joumalled for rotations about their axes, in end plates 24 and 26 which are suitably supported, as for example, on a center post 28. The rolls 2! are rotated about their respective axes by any suitable gear train 30 driven by a motor M. The bearings 32 of the rolls 22 are self-aligning and are such as to permit a slight skewing of the axes oi some or of all of the rolls relative to the axis of the center post or relative to a central fixed imaginary axis. The skewing of the axes of the rolls causes a filament wound afew times about one end of the reel, upon rotation of some or all of the rolls, to form a helix 34 which will move, longitudinally of the reel, towards the other end of saidreel.

portion As the filament moves from the right to the left hand end of the reel of Fig. 1, it is subjected to whatever liquid and other treatments may be desired, and the wet filament should be dried before it leaves the left hand end of the reel as shown in Fig. 1.

To this end, I provide a heating element formed of a coil 38 which may be heated electrically, by steam or otherwise, in any suitable manner not shown. The coil 36, which has any desired number of turns and is of any desired capacity, is positioned at the desired point along the length of the reel depending on attendant circumstances. In practice, and as shown, it is preferable that the heating element be placed as near the left hand end of the reel as may be consistent with adequate drying of the filament. In other words, the nature and rate of movement of the filament, the length and the diameter of the reel, and the quantity and nature of the moisture contained in the filament, as well as the practicable capacity of the heating element and the degree of drying to be attained are all considered and the heating element is so located relative to the reel that the filament will be adequately dried while travelling from the point at which the heating element begins to the left hand end or the reel. The space on the reel between the heating element and the end plate 24 is available for processing of the filament as maybe desired.

In order to establish a temperature gradient which is coordinated with moisture content of the filament, the heating element is formed so that its coils at the beginning of the drying zone are relatively closely spaced and so that the coils thereof are progressively further apart as the end of the drying zone is reached. This permits application of maximum heat with no thermal damage to the filament. As shown in Fig. 2, the heating coil 36 is positioned inwardly of a circle drawn through the axes of the rolls 22 so as to radiate heat outwardly against the rolls and the filament 'on the rolls. The heating coils are preferably bent to provide convex portions 38 which are disposed between the rolls 22 and concave portions 40 which register with the corresponding inner portions of the rolls themselves. By this arrangement, the portions 38 of the coil radiate heat primarily against the filament as it passes across the spaces between adjacent rolls and the portions 40 of the heating coil radiate heat primarily against the rolls themselves, whereby the filament is dried by radiated heat, by heated air and by contact with the heated portions of the rolls.

As shown in Figs. 2 and 3, the apparatus further includes a plenum chamber 42 which is positioned within, and which is preferably coextensive with, the heating coil 36. The plenum chamber 42 is supplied with air under pressure from any suitable source of supply, not shown, and it is provided with slits or other outlets 44 through which the air is blown around and between the heating coils and against the filament on the rolls. The air supplied to the plenum chamber may be predried by being passed over a moisture absorbing medium, or it may be preheated, or both. In any event, the air heated by contact with the heating coils and the heat radiated by the coils directly against the rolls and the filament combine to evaporate the moisture present so that the filament is sufilciently dried by the time it reaches the left hand, or delivery, end of the reel.

In order to conserve the heat and to prevent the heat from reaching the remaining portion of the reel, the heating zone is confined between two baflle plates 46 and 48. As will be seen from Fig. 2, the baflle plates are shaped to provide outer portions 50 which project between the rolls and concaved portions 52 which register with the inner portions of the rolls.

The delivery ends of the rolls are stepped, as shown in Fig. 1, so as to allow the filament to shrink during the drying stage and thus minimize shrinkage of the finished yarn and flanges 54 are provided to prevent the filament from falling off the delivery ends of the rolls.

In order to reduce the moisture content of the filament as much as possible at or just prior to the commencement of the driving action, I provide one of the lowermost rolls 32 with a stub shaft 58 which carries a gear 58. The gear 58 meshes with a gear 60 on one end of a shaft 62. The other end of the shaft 62 carries a resilient squeegee roll 64 which bears against the portion of the roll which, as shown in Figs. 1 and 3, corresponds to the beginning, or the right hand end of the heating coil. The squeegee roll 64 frictionally engages a wringer roll 66 which is fixedly mounted on a freely rotating shaft 68. The coil 64 exerts a squeezing action against the filament as it passes around the lower portion of the adjacent roll 22 in order to remove the film of liquid adhering thereto, as much as possible, and the roll 66 serves to remove, as much as possible, the film of liquid adhering to the roll 64. By the action of the rolls 64 and 66, a substantial amount of moisture is removed by mechanical means thus reducing, to that extent, the moisture to be removed by evaporation.

In the drawings I have shown only one squeegee roll arrangement and I have applied it to one of the lowermost rolls where, due to gravity and centrifugal action, the liquid tends to collect. However, it is to be understood that the wiping or squeegee roll assembly can be applied to any other, or to all, of the rolls.

The shafts B2 and 68 are journalled in suitable bearings 72, which are suitably supported in position.

From the foregoing it will be seen that a considerable, if not the major portion of the liquid is removed by the squeegee roll just as the filament enters the drying zone. This makes it pos sible to evaporate residual moisture while the filament moves through the relatively short drying zone without slowing down the rate of movement of the filament and without using excessive heat. It will also be seen that by the arrange-' ment of the heating coil the heat input varies directly with the amount of moisture present thus improving the efficiency and guarding against injury to the filament or to the reel.

In Fig. 4 I show another embodiment in which the ends of the rolls on which the filament is dried are tapered instead of being stepped. The taper of the rolls is such as to permit the desired shrinkage but it is so graduated that the helices moving thereacross will not slip.

By driving the squeegee roll 64 from the gear 58, the rotation of the squeegee is synchronized with the rotation of the rolls forming the thread advancing device. The purpose of this arrangement i to prevent lag between the rolls 84 and 22 and thus eliminating any drag on the filament. In other words, the filament is not subjected to friction or pull in any direction and is merely subjected to a squeezing action at the moment that it passes between the peripheries of the rolls l6 and 22.

What I claim is:

1. Apparatus including a thread storing and advancing reel, means for causing a wet filament to move, in the form of a helix, longitudinally of said reel, means for applying a squeezing action to the filament as it moves in contact with a predetermined portion of the reel, and a heating coil disposed within said reel for radiating heat outwardly against said filament and said reel, the convolutions of the filament being more closely spaced near the point where the squeezing action is applied and progressively more widely spaced in the direction of the end of the reel.

2. The structure recited in claim 1 together with means substantially coextensivewith said heating element and surrounded by said coils for blowing air past said coils and against said filament.

3. Apparatus including a thread storing and advancing reel formed of a plurality of elongated rolls and adapted to cause a wet filament wound thereabout to move, in the form of a helix, longitudinally of the reel, means for applying a squeezing action to said filament to remove liquid therefrom, a heating coil disposed inwardly of said reel and extending from the point at which the squeezing action is applied to the adjacent end of the reel, and blower means substantially coextensive with and disposed within said coil for blowing air radially outwardly against said coil and said helix, the portions of said rolls corresponding to said coil being tapered toward the end of the reel.

4. Apparatus including a thread advancing device formed of a plurality of elongated rolls with the thread passing around all of said rolls, driving means for rotating said rolls, a rotary squeegee roll adapted to exert pressure against said filament as it passes over one of said rolls, and actuating means for rotating said squeegee roll synchronously with said elongated rolls.

5. The structure recited in claim 4 in which the squeegee roll is rotated by the driving means which rotates the rolls of the thread advancing device.

6. The structure recited in claim 4 together with an auxiliary, freely rotatable roll, engaging, and rotated by, said squeegee roll for removing liquid from said squeegee roll.

HARRY A. KULJIAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,983,795 Fumess Dec. 11, 1934 2,204,603 Kline et al June 18, 1940 2,309,771 Jordan Feb. 2, 1943 2,319,812 Gram May 25, 1943 2,420,399 New May 13, 1947 2,465,214 Ewing Mar. 22, 1949 2,504,703 Kuljian Apr. 18, 1950 

